Plant biologists have made important strides in recent years in understanding the mechanisms that control flower development in higher plants. A large amount of the recent research on flowering has involved studying the effects of mutations that disrupt, block, or otherwise alter flower development in mutant plants. Most of this research has involved inducing mutations that produce mutant floral phenotypes in the model organism Arabidopsis thaliana and then identifying the gene that is responsible for the mutant floral phenotype.
Many of the regulatory genes that have been identified from Arabidopsis plants having mutant floral phenotypes are MADS box transcription factors that act at early stages in the organ developmental program (Riechmann and Meyerowitz (1997) Biol. Chem. 378:1079-1101; Theiben, et al., (2000) Plant. Mol. Biol. 42:115-149). In angiosperms, many of the genes of the MADS family are involved in different steps of flower development, most notably in the determination of floral meristem and organ identity (Riechmann and Meyerowitz (1997) Biol. Chem. 378:1079-1101).
While the research on the regulatory genes that control flowering in Arabidopsis thaliana and other angiosperms has provided biologists with fundamental knowledge of flower development, additional research on regulatory genes such as MADS box genes is needed to improve our understanding of the unique aspects of flowering in economically important crop plants, particularly those crop plants in which the seeds are the most important component of agricultural yield. Because seeds are produced from flowers, elucidating the biological mechanisms that control flower development in crop plants may lead to strategies for improving agricultural productivity by increasing seed or grain production in important crop plants such as, for example, maize, wheat, rice, soybeans, sunflower, and cotton.
Given the world's increasing human population combined with the ever diminishing amount of the world's land that is available for agricultural, increasing agricultural productivity is a paramount challenge facing humankind. The development of new strategies for the production of improved crop varieties that have increased yield and/or other desirable traits is needed to aid in meeting this paramount challenge.